Temperature is used to measure the output of a production process. When the process is in control , the mean of the process is 128.5 and the standard deviation is 0.4
a. construct an x chart if samples of size 6 are to be used.
b. is the process in control for a sample providing the following data?
128.8 128.2 129.1 128.7 128.4 129.2
c. is the process in control for a sample providing the following data?
129.3 128.7 128.6 129.2 129.5 129.0